I don't ignore it, I just don't interpret it the way you do.
Numerous characters commented on Luffy/Zoro's/Sanji's monstrous level of strength throughout the series, yes, and in this case Caribou called them the monstrous 3 because they just defeated the Kraken in front of his eyes. But Caribou doesn't know anything about the others, same case as with any other random fodder marine who calls Zoro "the captain", because he simply doesn't know better.
The only characters who can effectively judge are the other crew members, and they only made a distinction between the weak members and the "monsters".
For example Nami in this panel:
Or Chopper in this one:
But whatever, these times are officially over since the timeskip. Usopp openly stated that he isn't part of any weakling trio anymore and proved it with his recent battle. Same for Chopper, who said that he won't be a burden to anyone (but a real asset).
Now, I too believe that Sanji and Zoro have a special role when it comes to fighting, simply because they had to fight for the crew along Luffy for so many battles now (mainly because the rest was not capable of doing so).
But times change. The crew doesn't consist of merely 3 powerhouses anymore who have to shoulder all the work. Thats why me and a few others believe that the monster trio as we know it is dead, and if it isn't it will be the moment Jinbe joins.
The thing I don't understand is why this is a problem?
Sanji and Zoro will ALWAYS be at Luffy's side when shit goes down, mainly because of their fighting personalities. What is the problem to add (for example) Jinbe to that? Or Franky? Or Chopper?